Punch



R. E. VALENTINE PUNCH Filed Jan. 19, 1944 Oct. 3, 1944.

Patented Oct. 3, 1944 PUNCH Ralph E. Valentine, Buffalo, N. Y., assigner ton Curtiss-Wright Corporation, a corporationl of Delaware Claims.

This invention relates to a tool characterized by features which adapt it particularly, although not necessarily, for punching a part to mark thereon the locations of, or to form directly therein, holes which will be aligned with preformed concealed holes in a mating part.

In the manufacture of aircraft, it is frequently impracticable to pre-drill certain parts which are to be fastened to mating parts. For example, in the installation of cowlings, llets, cle-icing boots and the like, it is feasible, owing to the slight variations in the contours of the mating parts, to pre-drill only one of such parts, the other being drilled after the two parts have been fitted. In this way proper alignment of the holes which are to accommodate the fastenings is insured. To locate the centers of the holes in a part to be drilled, it has heretofore been the practice to scribe circles about the pre-drilled holes. The undrilled mating part is then fitted and temporarily secured in place over the predrilled part and while so tted and secured, intersecting arcs of the same radius as the circles on the pre-drilled part and having their centers located in spaced relation around the circumferences of said circles, are scribed on the part to be drilled. 'Ihe arc intersectionsthus provided indicate on the undrilled part the locations at which holes drilled, punched, or otherwise formed in such part will be in alignment with the holes in the pre-drilled part. The undrilled part is then removed and after being drilled or punched at the points indicated is permanently secured in place.

One object of the present invention is to provide a tool which may be availed of to mark the locations of, or to form directly, holes in one part which are accurately aligned with pre-formed holes in a mating part, thereby avoiding the necessity of scribing the parts in the manner described, and hence eliminating the operations involved and the possibility of error attendant with such operations.

A further object is to provide a tool which will act uniformly regardless of the manner in which it is operated.

A still further object is a novel design and arrangement of the parts of the tool, whereby to obtain simplicity in construction and ease of operation.

The invention is illustrated in the accompanying drawing in which:

Figure 1 is a side elevational view of a tool embodying the features of the invention.

Application January 19, 1944, Serial No. 519,065

tool.

Figure 3 is an end View of the tool. Figure 4 is a detail section taken along line 4--d of Figure 1. Y

Figure 5 is a sectional view of a modified form v of tool.

The tool, as illustrated, includes a tubular body 9, one end of which is closed by a threaded plug I0. The opposite end of the tubular body 9 is suitably secured in a socket `II formed in a headpiece l2, the bottom Wall of the said socket being formed with an opening I3. 4An anvil I4, which is carried by the head-piece I2, is formed with a tongue portion I5, the latter being spaced from the lower face Aof the head-piece Yand ycarrying a pilot pin I6. A punch element I'I occupies the tubular body 9, the said element being formed or provided with a plunger-like body I8, a head I9 and a shank 20, the tip of the shank, in the embodiment illustrated in Figures 1 and 2, being pointed and the axis of the shank being in alignment with the axis of the pilot pin I6. A main spring 2I is located between the plug II) and the head I9 of the punch element while a secondary spring 22 is located between the lower end of the body of the punch element andthe end wall of the socket I I. The two springs normally support the punch element in the location illustrated in Figure 2 of the drawing, in which location the tip of the shank 2U is retracted with respect to the outer face of the head-piece and is located Within and substantially centrally of the opening I3. An actuating lever, indicated at'23, is forked at one end, the branches of the forked end straddling the head-piece I2 and being pivotally connected thereto by a pin 24. 'I'he opposite or free end of the actuating lever provides a handle. A spring 25 which is connected at one end to the head-piece I2 is connected at its opposite end to an arm 26. One end `of the latter is pivotally connected to a pin 2l carried by the actuating lever while the opposite end which is notched extends through a longitudinally extending slot 28 formed in the wall of the tubular body 9 and engages the under side of the head I9 of the punch element. The spring 25 acting through the agency of the arm 26 normally holds the actuating lever in the extended, or full-line, position illustrated, in which position the branches of the forked end of the lever engage shoulders 29 o the head-piece I2.

In the use of the tool the tongue portion of the anvil is inserted under the'edge of jan undrilled sheet 3D, as best shown in Figure 2, to

Figure 2 is a longitudinalsection through the cause the pilot pin I6 to enter a pre-drilled hole 3I in a mating sheet 32. The lever 23 is then actuated by4 moving the handle thereof toward the tubular body 9, the limit of such movement being reached when the end of the handle engages the said body, as indicated fin dotted lines in Figure 1. When the,y lever 23 is actuated in the manner described the resultant movement of the arm 261s transmitted to the punch element and the latter is moved axially toward the plug Il), compressing and hence loading the spring 2l as it moves in such direction. Asv the handle portion of the lever 23 approaches the tubular body 9, the nose portion, 3,3 of the arm 26 engages an inclined end wall 34 of the slot 28, The free end of the said arm is thereby caused to swing outwardly and the head I9 of the punch element is released. The spring 2| is thereupon operative to propel the punch element rapidly in the direction of the part to be marked. Although the secondary spring 2|. tends slightly to decelerate the punch element after the latter reaches its normalposition, its inertia is great enough to carry it welll beyond its normal position. The shank of the punch element, therefore, is projectedthrough the opening I3 against the action of the spring 22 and the pointed end thereof is caused to strike sharply and form an indentation in the surface of the sheet 30. The travel of the punch element being arrested by its engagement with the sheet 30, the spring 22 restores the punch element. to its normal position. The lever 23-is then released-to permit the spring 25 to return to its-original position, the arm 26 riding rst over the corivolutions of the, spring 2| andthen over and-under the head of the punch element .so that when the lever is again actuated the punch element will be caused to function in the manner described.

It will be apparent from the foregoing that when the tool is employed in the manner described the sheet -willbe marked to indicate the location of the center o f a hole which will be in exact alignment with the pre-drilled or punched hole in which the pilot pin I6 is located. As the spring 2|iis always loaded to the same degree when the lever 23-is actuated, the indentations which are formedin theV sheet 30 will all be of substantially'the same size, depth and appearance.' The Aactionof the tooltherefore, will be uniform regardless of-the care or 'speed with which it is actuated.-

Insteadof marking .the sheet 30to indicate the locations ofthe holes, the latter'may, if desired, be formed directly by theV tool, as illustrated in Figure '51.5 Insuch case the'pilot pin I6 is carried by a ,die element 35.- The latter is accommodated in a suitable recess formed in the tongue portion ofthe anvil-I4 in such a manner that the pilot'pin may be utilized as described in connection' withthe embodiment shown inA Figure 1. The end-of rthe shank 2|J in this embodiment is `formed with a cutting edge which,

cooperates with a cutting edge on the die element 35. An opening 36 in the die element, which the shank portion of -the punch element enters in the punching operation, accommodates a pad 31 of rubber or other resilient material for ejecting from the opening the slugs formed in the use of the tool. The holes punched inthe sheet 30 by the toolwill, for the 'reasons'heretofore4 noted be in alignment with the ,holes in the sheet 32.l

yApart from the use of the toolin the manner an'd 4forthe purposefdescribed,the tool may also be availed of to punch a part at a predetermined distance from a marginal edge of the part. ln such case the inner wall of the body portion of the anvil is engageable with the marginal edge of the part to gauge the distance from such edge at which the punch element is to mark or perforate the part, there being no occasion, of

course, when using the tool in this manner to utilize the pilot pin.

I claim as myv invention:

1. A tool for use in connection with the forming of a hole in one part which is aligned with aA pre-formed hole in a mating part, said tool including a body, means carried by said body which may. bepositioned under said first mention/ed:` part, a, pilot pin carried by said means which is adapted to be inserted in said preformed hole to locate said body in the properrelation with respect to said first mentioned part,. a punch element carried by said body for acting: on said rst mentioned part, resilient means, means for loading said resilient means, and'4 means for utilizing the energy-thereby stored in. said resilient means toactuate said punch ele ment.

2. A tool for-usein connection With the forming of a hole in one part whichis aligned' with:` a pre-formed-holein a mating part, said tool in cluding a body, means. carried-by saidbody Which; may be positioned. underv said.v first mentioned' part, a pilot pin carried bylsaid means to locate: saidbody in the proper relation with respect to; saidA first mentioned part, a punchv element car-- ried by said body. inl alignmentwithsaid pilot..

may be positioned under said first mentioned` part, a pilot pin. carried .by saidv means which is.

adapted to be inserted in said-.pre-formed hole to locate saidbody iny the .proper relation with respectto saidfrst mentionedpart, a punch element carried by saidbody for acting upon said first -mentioned part; resilient ;means, and means for retracting said..punch element to compress and thereby load.` said resilient imeans, said punch element bengthereafter releasableto permit` said resilient means-to) actuateit.

4. A tool for use in connection with the forming of a hole in onepart which is aligned with` a pre-formed vhole ina mating-part, said. tool. in-

cluding a body, meanscarried by said body which may be positioned 1 under said first mentioned* part, a pilotpincarriedby-saidmeanswhich is adapted to be `inserted inasaid pre-formed hole tolocate-said bodyv in Ithe-properrelation .with respect to said. iirstmentionedpart, apunch element carried by said body for acting-upon-saidI rst mentioned part,v resilient -means,-and means for y.retracting said .punch;.element to compress and thereby load said resilient means, said last named means releasing saidy punch element when itwhas vbeen retracted to a predetermined position, whereby to permit said-resilient means to` actuate it. y

5. A .tool for use in connection with the -formin g of a hole in one part which" is aligned with a. pre-formed hole in a Amating part; said tool in cluding a body, Vmeans carried by said body which;

may be positioned under said rst mentioned part, a pilot pin carried by said means which is 'adapted to be inserted in said pre-formed hole to locate said body in the proper relation With respect to said rst mentioned part, a punch element carried by said body for acting upon said rst mentioned part, resilient means, means for retracting said punch element to load said resilient means, and means for automatically releasing said punch element when said resilient means has been loaded to a predetermined degree, whereby to permit said resilient means to actuate said punch element.

6. A tool for use in connection with the forming of a hole in one part which is aligned with a pre-formed hole in a mating part, said tool including a body, means carried by saidbody which may be positioned under said first mentioned part, a pilot pin carried by said means Which is adapted to be inserted in said pre-formed hole to locate said body in the proper relation With respect to said first mentioned part, a punch element carried by said body for acting upon said first mentioned part, resilient means, means for retracting said punch element to load said resilient means, and means for automatically releasing said punch element when it has been retracted to a predetermined limit, whereby to permit said resilient means to actuate it.

7. A tool for use in connection with the forming of a hole in one part which is aligned with a pre-formed hole in a mating part, said tool including a tubular body, means carried by said body which may be positioned under said first mentioned part, a pilot pin carried by said means which is adapted to be inserted in said pre-formed hole to locate said body in the proper relation With respect to said rst mentioned part, a punch element in said body, said punch element having a plunger-like body and a shank portion for acting on said first mentioned part, resilient means, means for retracting said punch element to load said resilient means, and means for automatically releasing said punch element when it has been retracted to a predetermined limit, whereby to permit said resilient means to actuate it 8. A tool for use in connection with the forming of a hole in one part which is aligned with a pre-formed hole in a mating part, said tool including a tubular body, means carried by said body which may be positioned under said rst mentioned part, a pilot pin carried by said means which is adapted to be inserted in said pre-formed hole to locate said body in the proper relation with respect to said first mentioned part, a punch element in said body, resilient means acting upon said punch element in opposite directions to hold the Iatter in a predetermined position in said body, means for retracting said punch element to load one of said resilient means, and means for releasing said punch element when it has been retracted to a predetermined limit, Whereby to permit said last mentioned resilient means to actuate it, said last mentioned resilient means being operative in so doing to advance said punch element beyond said predetermined position.

9. A tool for use in connection with the forming of a hole in one part which is aligned with a 4 pre-formed hole in a mating part, said tool including a tubular body, means carried by said body which may be positioned under said rst mentioned part, a pilot pin carried by said means which is adapted to be inserted in said pre-formed hole to locate Said body in the proper relation with respect to said rst mentioned part, a punch element in said body, said punch element having a plunger-like body and a shank portion for acting upon said rst -mentioned part, resilient means acting upon the body of said punch element in opposite directions to hold the latter in a predetermined position, means for retracting said punch element to compress and thereby load one of said resilient means, and means for automatically releasing said punch element when it has been retracted to a predetermined limit, whereby to permit said last mentioned resilient means to actuate it, said last mentioned resilient means being operative in so doing to advance said punch elementbeyond said predetermined position.

10. A tool for use in connection with the forming of a hole in one part which is aligned with a pre-formed hole in a mating part, said tool including a tubular body, means carried by said body which may be positioned under said first mentioned part, a pilot pin carried by said means Which is adapted to be inserted in said preformed hole to locate said body in the proper relation with respect to said rst mentioned part, a punch element in said body, said punch element having a plunger-like body and a shank portion for acting upon said first mentioned part, resilient means acting upon the body of said punch element in opposite directions to hold the latter in a predetermined position, a lever pivotally connected to said rst mentioned body, an arm pivotally connected to said lever and engageable with said punch element, said lever being movable toward said first mentioned body to cause said arm to retract said punch element and thereby load one of said resilient means, means for automatically eiecting the release of said punch element when it has been retracted to a predetermined limit, whereby to permit said last mentioned resilient means to actuate said punch element, said last mentioned resilient means being operative in so doing to advance said punch element beyond said predetermined position, and means for restoring said lever to its original position when it is released.

RALPH E'. VALENTINE. 

